Quickest way to lower your Testosterone
The devastating effect of heat on the testicles reveals the power of ball icing
Over the past two decades, American men’s testosterone has rapidly declined.
Thomas Travison, PhD, author of the paper A Population-Level Decline in Serum Testosterone Levels in American Men says they observed an overall decrease in testosterone in men over the years across a wide range of ages.
Worse, sperm concentrations have cut in half since 1973.
As you’d expect, fertility rates decline as testosterone does.
There are many factors to this decline in testosterone, sperm quality and fertility. One suspect is our more sedentary lifestyles. We’ve all heard about how bad a sedentary lifestyle and sitting for hours on end is awful for our health. Pretty straightforward: move less, get fat.
But what if sitting itself had a direct effect on men’s testicles, testosterone levels and sperm production? Imagine that while you sat down, you had a tiny mouse wedged between your thighs and the chair cushion. That mouse would probably be pretty damn hot. Well, this is basically what’s happening to your testicles when you sit down: they’re heating up. Men may be told ‘come on, your balls aren’t that big,’ or criticized for assuming such a childish ‘dominance’ posture when they spread their legs wide when sitting - what some people call ‘manspreading.’ However, it may just be an instinctual urge to keep the testicles cooler.
The scrotum has a natural cooling mechanism that works by increasing the exposed surface area. This is why your testicles hang lower when it’s hot outside. Your testicles simply don’t work as well when they overheat.
Several studies have found that even a small increase in ball temperature leads to dramatic degradation of sperm quality. High temperatures affecting sperm quality has been known since the 1920’s. A 1967 paper looking at the effect of a mere 0.8° C increase in ball temperature starts by saying:
In both beast and man, testes exposed to temperatures that exceed physiologic limits suffer suppression of spermatogenesis. …it has been clearly shown that the deliberate application of heat to the scrotum brings about a reduction in the sperm counts of normal, euspermic subjects.
In the study, they maintained a group of 10 healthy men’s balls at +0.8° C for 15 hours per day. They observed an 80% reduction in sperm count over the 2-3 month period of the study.
Another 1985 study tried +2° C on the balls for 15 hours a day, this led to a 90% reduction in sperm count. Luckily the effect was reversed after 3-4 months of giving the balls a break from the heat. By the way this study was suspecting scrotal heating could be a form of contraceptive.
You can find plenty more studies like this that show that the balls do not like heat.
What else might increase your ball temperature? Tight underwear. This below graph is from a study titled Mild induced testicular and epididymal hyperthermia alters sperm chromatin integrity in men and shows that sperm count declines when men wear tight underwear. This is thought to be the result of not allowing the testicles to freely hang and maintain distance from the body. Being pressed up against the body heats up the testicles. Sperm count increased when the subjects stopped wearing the tight underwear.
This study notes that if you want to preserve the integrity of a semen sample itself, it needs to be kept at a very cool 20 degrees celsius. In another study, it was found that the hotter the testicles in infertile men, the more messed up their sperm was:
In the infertile men, it was found that the higher the scrotal temperature, the more alterated the sperm characteristics.
What about testosterone?
Having top-notch sperm is cool and all, but for us guys not trying to have a baby, we’re more concerned with testosterone. Does heating really mean bad ball function overall or it simply that sperm itself doesn’t handle heat well, so testosterone isn’t affected?
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